Electric-arc lamp.



Patented May 24, 1910.

. nvewtoz 41 0 JV" athwmug L. W. PULLEN ELECTRIC ARC LAMP.

APPLICATION FILED 10110.12, 1906.

wammm UNITED STATES PATENT OFFICE.

LEON w. PULLEN, or CAMDEN, NEW JERSEY, ASSIGNOR, BY MEsNE ASSIGNMENTS,

T0 WALDRON CLARK MANUFACTURING COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC-ARC LAMP.

Specification of Letters Patent.

Application filed December 12, 1905.

Patented May-,24, 1910. Serial No. 291,390.

To all whom it may concern:

Be it known that I, LEON W. PULLEN, of Camden, county of Camden, State of New Jersey, have invented an Improvement in Electric-Arc Lamps, of which the following is a specification.

My invention has reference to electric arc lamps and consists of certain improvements which are fully set forth in the following specification and shown in the accompanying drawings, which form a part thereof.

The object of my invention is to provide a construction of lamp which shall be very steady in operation, respond quickly to change in current, shall be inexpensive to construct and require a minimum amount of trimming.

My invention consists of a reservoir containing a fluid such as mercury surrounded by an electro-magnet or solenoid, combined with a plunger float received in the reservoir and in contact with the mercury whereby it is actuated by the attraction of the magnet or solenoid to move and regulate the movable carbon to control the arc; also in said structure when provided with a brake device on the plunger which while permitting a quick limited movement to said plunger will only permit the plunger to move slowly in the reservoir for any extended movement; also in providing sealed yet movable globes to rotect the carbons from the destructive action of the air; and in many details of construction, which together with the features above specified will be better understood by reference to the drawings, in which: I

Figure 1 is a sectional elevation of an electric arc lamp embodyin my invention; Fig. 2 is an enlarged view 0 a portion of Fig. 1;

p and Fig. 3 is a sectional elevation of a modification.

A is the stand or general frame and may be made in any suitable manner. It is provided at the top with a head B consisting of a series of stamped sheet metal plates in circular flanged form of different diameters so that when fitted together as shown they form at the center an annular recess 1) and a series of concentric flanges D D extending upward at the outer parts of said plates which form twoconcentric narrow grooves into which the bases of the globes O C fit as shown so that the glode C fits wholly within the globe C. The bases of these globes may be sealed against passage of air by use of mercury in the grooves in which they fit as indicated at (Z. In this case the plates B should be made of sheet iron. If desired the flan es D D may be relied upon as baflles and the mercury omitted, though this would not make as tight a joint.

Depending from the center of the head B is a reservoir E formed of tubular shape and partly filled with mercury T. Surrounding this reservoir may be a similar tube E of copper or other metal and inclosing this is the solenoid winding F in which the number of the coils increases as the bottom is approached. r

G is a plun er of sheet iron in open tubular form an moves upand down in the mercury T within the reservoir E. To make this plunger light so that its lower part has the requisite buo ancy, I provide it with asbestos lining at G In this way the plunger will rise well up in the mercury and sustain itself when necessar The upper end of this plunger is provi ed with a carbon clamp g carrying the lower carbon H. The upper carbon H is carried in a clamp 2' on the upper end of an arm I within the globe C and secured to the head B by an insulated joint I.

The plunger G is uided through the insulating bushing or isk L which is preferably made of lava and fitted within the annular recess 25 of the head B. The lower end of the plunger is provided with a plug J having a small hole through which the mercury may flow into and out of the plunger according as to whether it is descending or ascending. Surrounding the plug J and with freedom of vertical play forabout a sixteenth of an inch is a brake bushin K of lava which loosely fits the interior 0 the tubular reservoir E. This bushin acts as a guide for the lower end of the p unger G within the tubular reservoir E and at the in case of variations of current or imperfect carbons. The plunger produces very little displacement of the mercury because the mercury is allowed to flow both inside and IOU ters Patent, is:

outside of the plunger. The plunger is acted upon by a solenoid in which the winding is 0 few turns at the top and of gradually increased number of turns as we descend so as to produce an even pull on the plunger during .its entire movement from highest to lower position.

The life of the carbons is increased by the use of the double globes both of which are sealed so that no cold air containing oxygen can enter to the arc chamber within the inner globe.

Current is supplied by wire L which includes the resistance N and solenoid and after traversing the parts it is delivered to the arm I and thence to the upper or positive carbon. The current then passes throu h the arc to the lower carbon, thence to t e plunger G, mercury and reservoir E and leaves the lamp by wire M. The resistance N is carried upon a slate support N in the base of the lamp frame. If desired, an additional shunting resistance P 'may be employed which may, under control of a switch P, bridge-the solenoid and control the arc to adapt the lamp for internal adjustment and to suit circuits of different voltages or current strength.

. In place of employing the bushing K, the walls of the tubular reservoir E may be provided with an annular rib K as shown in Fig. 3 to form a guide and also a controlled or braking passa e for the mercury. This prevents too su den displacement of the mercury which would have a tendency to permit the too rapid ulling down of the plunger by the solenoid and cause it to produce a rupture of the arc and a rheotome action which is highly objectionable.

It is evident that while I have shown my lamp as a standingor table lamp, it may be readily adapted for suspension as my invention is not limited to any manner of supportin or suspending the lamp.

Whi e I have shown a construction of lamp embodying my invention which is adaptedfor commercial use, I do not limit myself to the details thereof as they may be modified in various ways without departing from the spirit of the invention.

Having now described my' invention, what I claim as new and desire to secure 'by Let- 1. In an arc lamp, the combination of a tubular reservoir and containing mercury, a solenoid surroundlng the reservoir, a hollow .tubular plunger of magnetic material floating in said mercury and having a straight central contracted vertical openin in its bottom to cause the mercury to pass into and out of the interior and maintaining the centralposition of the plunger in the reservoir, an electrode holder carried by the plunger, and an electrode holder to or from which the plunger moves.

low-plunger of iron having a buoyant bodysecured to its lower part and floating in said mercury and having at its .top means for moving an electrode and an annular bushing surrounding the lower portion of the plun-- ger and having a sliding connection therewith for permitting a small but quick movement to the plunger while the bushing acts as a guide and loose piston to retard the free movement of the plunger over great distance, an electrode holder to or from which the plunger moves, and electric conductors including the solenoid plunger and electrode in series. I

3. In an arc lamp, a head for the globes consisting of a series of circular plates having flanges, the said plates being clamped together to bring the flanges concentric so as to form narrow concentric grooves adjacent to the perimeter and a shouldered portion at the center, combined with two globes one inclosing the other and having their rims respectively snugly fitting into said grooves, and a central insulating guide for the movable carbon holder su ported by the central shouldered portion 0 the circular plates.

4. In an arc lamp a head consisting of a series of superimposed flanged plates-of dif ferent diameters in which the flanges form two annular dee concentric grooves each containing a sea ing body of mercury, a tubular central part for uniting the several flanged plates, a central closed globe having its lower rim fitted into the inner of said grooves, an outer inclosing globe surrounding the inner globe and having its lower rim fitted into the outer of said grooves, clamps for electrodes within the inner globe, and electro-magnetic means for adjusting the electrodes to maintain an arc.

5. In an arc lamp, a head for supporting mercury and guided by the bushing for regulating thearc of the electrodes, a bushing surrounding the lower part of the plunger and loosely fitting the tubular reservoir both for retarding and guiding it in its movement, and an electrically energized solenoid surrounding the reservoir for magnetizing the plunger.

7. In an arc lamp, the combination of a tubular reservoir containing mercury, an insulating guide bushing at its top, a tubular plunger of magnetic material floating in the mercury and guided by the bushing for regulatingthe arc of the electrodes, a loose bushing surrounding the lower part of the plunger with freedom of slight movement thereon and loosely fitting the tubular reservoir both for retarding and guiding it in its movement, and an electrically energized solenoid surrounding the reservoir for magnetizing the plunger.

8. The plunger for operating the electrode of an arc lamp formed of a tube of uniform magnetic cross section open at the bottom through an orifice of small cross section and containing on its interior a tubular fioat of nonmetallic substance.

9. The lunger for operatin the electrode 20 of an arc lamp formed of a tu of uniform magnetic cross section open at the bottom through an orifice of small cross section and containing on its interior a tubular float of asbestos.

In testimony of which invention, I hereunto set my hand.

LEON W. PULLEN.

Witnesses:

R. M. KELLY, M. J. EYRE. 

